Large animal euthanasia

Question 1

Euthanasia

Answer 1

Greek for good death
Euphemisms: put down, put to sleep
Must relieve fear and apprehension
Must induce unconsciousness as rapidly as possible, ensuring minimum pain and suffering
1. sedation/tranquilization
2. unconsciousness
3. cardiorespiratory arrest

Question 2

Modes of action of euthanasia

Answer 2

Hypoxemia
Depression of the neurons vital for life
Physical damage to the brain tissue

Question 3

Reasons for euthanasia of large animals..

Answer 3

Food production
Pain and suffering (colic, fracture)
Intractable conditions/situation (hard to control or deal with)
-race track fracture “break down injury” emaciated neglect/feral cases, hit by vehicle, fallen in hole, trailer accident.
Chronic incurable conditions (laminitis, arthritis, deformities, cancer)

Question 4

When is it time to euthanize?

Answer 4

Is the condition chronic and incurable?
Is the immediate condition a poor/grave prognosis?
is the animal a hazard to itself or its handler?
Will the animal require constant pain-reliving medication for the rest of its life?

Question 5

Approved methods for large animal euthanasia?

Answer 5

Injectable barbiturates
Captive bolt
Gunshot
Potassium chloride while anesthetized

Question 6

Injectable barbituates

Answer 6

CNS depression
-descending depression as the dose increases
Death occurs from respiratory arrest and myocardial hypoxia
Rapidity of death depends on animal oxygenation
Rapid onset of action, sooth induction of anesthesia, minimal side effects
Pentobarbital (100 mL IV for average size adult horse)
Thiopental (20-30 mg/kg IV)

Question 7

Captive bolt

Answer 7

Used when tissues must be free of drug residues
-Food animals
Used to produce unconsciousness
Followed by exsanguination
Three types (penetrating, non-penetrating and free bolt).

Question 8

Penetrating captive bolt

Answer 8

Currently the most effective type of stunning since it physically destroys the brain matter (increasing the probability of a successful stun) while also leaving the brain stem intact and thus ensuring the heart continues to pump during exsanguination.

Question 9

Penetrating captive bolt

Disadvantages?

Answer 9

The brain matter is allowed to enter the blood stream and possibly contaminate other tissue with BSE (mad cow disease)
Has largely been discontinued in commercial situations in order to minimize the risk of transmission of disease.

Question 10

Non-penetrating captive bolt

Answer 10

Action is similar to penetrating version, but bolt is blunt with a mushroom shaped tip.
Bolt strikes the forehead with great force and immediately retracts.
Concussion is responsible for unconsciousness.
Less reliable at causing immediate and permanent unconsciousness than penetrating types; however it has undergone a resurgence of popularity due to concerns of BSE
Should NOT be used as sole method of euthanasia
-follow with exsanguination

Question 11

Free Bolt

Answer 11

Used for emergency in the field euthanasia of large farm-animals that cannot be restrained.
Differs from a true captive bolt gun in that the projectile is not retractable, it is similar in operation to a powder-actuated nail gun or conventional firearm.
Capable of firing only when pressed firmly against a surface (typically the animals forehead) the device fires a small projectile through the skull.
Vet can either leave the animal to die from projectile wound or administer lethal drugs.

Question 12

Captive bolt (pigs)

Answer 12

Page 19

Question 13

Gunshot

Answer 13

32 caliber or larger
proper placement is absolutely necessary
NOT BETWEEN THE EYES!

Question 14

Potassium chloride

Answer 14

IV injection of 50 to 100mL of a saturated solution
Cardiac arrest and tissue hypoxia
economical
approved if the animal is unconscious or anesthetized!

Question 15

Unapproved methods..

Answer 15

ANY METHOD THAT DOES NOT INDUCE UNCONSCIOUSNESS BEFORE CARDIORESP DEATH.

• Electrocution
• Exsanguination
• Air embolism
• Hydrogen cyanide, CO2 ,nitrogen inhalation, curariform drugs, potassium choride.

Question 16

Hazards to consider with horse euthanasia

Answer 16

If not already recumbent, horse has to fall down.
Uncontrolled movement
Paddling of legs, poorly controlled kicking, muscle fasciculation’s
Eating of carcass if injectable barbiturates were used.
Ensure death!!! Absence of heart beat, respirations and corneal reflex.
Create a pneumothorax.

Question 17

Horse euthanasia safety

Answer 17

SEDATE!!!
Place a catheter 
Have a good help
Have an escape route
Use ropes if possible

Question 18

Disposal options

Answer 18

Bury on property.. legal? permit? equipment?

Haul away.. independent company.. take to land fill, rendering, simple/mass cremation, private cremation.

Question 19

Owner issues with horse euthanasia…

Answer 19

If its easier for the veterinarian to reach a decision to euthanize
-knowledge of medical conditions with poor/grave prognosis
-less sentimental attachment
-oath to relieve animal suffering
Cost (especially of disposal)
Aesthetic effects important!
-Strive to project professional image and caring attitude
-Perform euthanasia proficiently and expediently
-Promote client confidence and respect

Question 20

Insured horses

Answer 20

Is the horse actually insured?
DO NOT EUTH Without insurance COMPANY CONSENT/NOTIFICATION
Any restrictions to policy?
-most policies will not permit euth for loss of use or value
-horse must be suffering that it would be inhumane to keep it alive
DOCUMENT!
-date and name of person consenting to euth on behalf of insurance company
Is necropsy required?
-SERIOUS policy violation if company not given opportunity to perform an exam
-could compromise claim!!

Question 21

Regardless of the method used…

Answer 21

it should be RAPID, PAINLESS and STRESS FREE induction of unconsciousness.